JLG 450A_AJ Series II Service Manual - Manual (Page 174)

SECTION 3 - CHASSIS & TURNTABLE
3-134 – JLG Lift – 3121290
DTC 524- Oil Pressure Low
• Engine Oil Pressure.
• Check Condition- Key on, Engine on.
• Fault Condition- Engine oil pressure lower than expected
while engine has been running for a minimum amount of
time while engine speed is above some limit as defined in
the diagnostic calibration.
• Corrective Action(s)- Illuminate MIL and/or sound audible
warning or illuminate secondary warning lamp, generally
configured to derate the engine and trigger an engine
shutdown.
• Non-emissions related fault.
The ECM can be configured to monitor oil pressure through a
proportional transducer or through a switch. Oil pressure
monitoring is important to prevent engine damage due to low
oil pressure resulting in higher friction and lack of lubrication.
In addition, high oil pressure can be undesirable because it
can cause oil to leak past seals and rings, can be a result of a
restriction in the oil flow path, or can be a sign of a malfunc-
tioning oiling system.
For systems that use a transducer, this fault sets if engine oil
pressure is less than x psia and engine speed is greater than y
RPM after engine has been running for z seconds as defined in
diagnostic calibration. For systems that use a switch, this fault
can be configured two different ways. It may use a normally
closed switch or a normally open switch.
If switch is normally open, fault sets if circuit becomes
grounded.
If switch is normally closed, fault sets if circuit becomes open.
Go to Faults page in EDIS to determine how the input is con-
figured. (“Open=OK” is normally open and “Ground=OK” is
normally closed). The engine should be configured to derate
or force idle and/or shut down in the event of this fault to pre-
vent possible damage.